When the new lawn mower quit working, Carl’s anger toward

When the new lawn mower quit working, Carl’s anger toward it was unleashed and he kicked the gate and broke it.
a) Carl’s anger toward it was unleashed and he kicked the gate and broke it
b) Carl became angry and the gate was kicked and broke
c) Carl’s anger toward it was unleashed and it was broken when he kicked the gate
d) Carl became angry and he kicked the gate and broke it
e) Carl kicked the gate and broke it when it angered him

Please need help with following questions

The OA is D
Does D need comma between 2 independent clauses to be correct (FANBOYS rule?)

d) Carl became angry, and he kicked the gate and broke it
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12. Mr. and Mrs. O’Leary couldn’t get away from their grandchildren, and this is why they didn’t make it to the opening night of the new theater performance.
a) Mr. and Mrs. O’Leary couldn’t get away from their grandchildren, and this is why they couldn’t
b) The grandchildren of Mr. and Mrs. O’Leary wouldn’t let them go, so this is the reason
c) The fact that Mr. and Mrs. O’Leary didn’t want to leave their grandchildren is the reason why they didn’t
d) This being the reason why Mr. and Mrs. O’Leary didn’t want to leave their grandchildren and couldn’t
e) The problem was that Mr. and Mrs. O’Leary couldn’t leave their grandchildren and that is why they hadn’t

OA is C
is in C a Vague pronoun?
C) The fact that Mr. and Mrs. O’Leary didn’t want to leave their grandchildren is the reason why they didn’t make it
It is not clear who (Mr or Mrs O'leary) or their grandchildren didn't make it